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We compared the structural and optical properties of InAs/GaAs quantum dots grown by migration enhanced epitaxy, with and without arsenic, during indium deposition. The uniformity and size of the quantum dots are enhanced in a sample without arsenic. As a result, narrower and longer wavelength photoluminescence is observed in this sample. Furthermore, the thickness of the wetting layers is reduced by ∼20% in the sample without arsenic, and this result agrees well with the speculation that metallic indium has a smaller driving force for corrugating the InAs wetting layers before they are transformed from two-dimensional to three-dimensional layers. Additionally, the photoluminescence linewidth of the sample without arsenic is insensitive to the cryostat temperature due to two major factors: the reduced thickness of the wetting layers and the enhanced uniformity. In the sample with arsenic, however, the photoluminescence linewidth shows typical anomalies. [ABSTRACT FROM AUTHOR]

Salmonellosis is an important zoonotic disease that affects both people and animals. The incidence of reptile-associated salmonellosis has increased in Western countries due to the increasing popularity of reptiles as pets. In Korea, where reptiles are not popular as pets, many zoos offer programs in which people have contact with animals, including reptiles. So, we determined the rate of Salmonella spp. infection in animals by taking anal swabs from 294 animals at Seoul Grand Park. Salmonella spp. were isolated from 14 of 46 reptiles (30.4%), 1 of 15 birds (6.7%) and 2 of 233 mammals (0.9%). These findings indicate that vigilance is required for determining the presence of zoonotic pathogen infections in zoo animals and contamination of animal facilities to prevent human infection with zoonotic diseases from zoo facilities and animal exhibitions. In addition, prevention of human infection requires proper education about personal hygiene. [ABSTRACT FROM AUTHOR]

Effects of freezing on apoptosis and autophagy in embryos are poorly understood. This study introduces a simple and successful method (modified cut standard straw, M-CSS) for cryopreservation of mouse zygotes. Apoptosis and autophagy were investigated in cultured mouse blastocysts derived from vitrified zygotes using two vitrification containers (M-CSS vs 0.25-ml straw). The percentages of zygotes that survived and developed into blastocysts and the number of cells per blastocyst were higher in the M-CSS group than in the 0.25 ml straw group; whereas the rate of apoptosis in blastocysts was significantly lower in the M-CSS group than in the 0.25-ml straw group. The expression of the apoptosis-related gene Caspase 3 in blastocysts was higher in the 0.25-ml straw group than in the M-CSS group; however, there were no significant differences in autophagy between these two groups. Vitrified-thawed mouse zygotes were transferred into recipients. The percentage of recipients that became pregnant and the percentage of transferred zygotes that developed into live offspring were significantly lower in the 0.25-ml straw group than in the M-CSS (10.2% vs. 17.5%). In conclusion, the novel M-CSS procedure improves oocyte and embryo vitrification. The standard 0.25-ml straw vitrification procedure induces mitochondrial apoptosis in zygotes in an autophagy-independent manner.

The prevalence of type 2 diabetes has been increasing in Singapore and is a major risk factor for cardiovascular disease. Exercise training is an important therapeutic modality for managing glycaemic control and improving cardiovascular health among persons with type 2 diabetes. It may also help to prevent or delay the onset of this harmful condition. This review examines the evidence and possible mechanisms by which exercise training produces these benefits, and gives a brief review of appropriate exercise activities.

Background: Acute ischemic stroke in the distribution of the anterior inferior cerebellar artery is known to be associated with hearing loss, facial weakness, ataxia, nystagmus, and hypalgesia. There have been few reports on bilateral deafness and vertebrobasilar occlusive disease. Furthermore, previous reports have not emphasized the inner ear as a localization of bilateral deafness., Objective: To describe the presentation of acute ischemic stroke in the distribution of the anterior inferior cerebellar artery as sudden bilateral hearing loss with minimal associated signs., Design and Setting: Case report and tertiary care hospital., Patient: A 66-year-old man with diabetes mellitus developed sudden bilateral deafness, unilateral tinnitus, and vertigo 7 days before the onset of dysarthria, facial weakness, and ataxia. T2-weighted magnetic resonance imaging scans showed hyperintensities in the right lateral pons and right middle cerebral peduncle and a possible abnormality of the left middle cerebellar peduncle. A magnetic resonance angiogram showed moderately severe stenosis of the distal vertebral artery and middle third of the basilar artery. The patient's right limb coordination and gait improved steadily over several weeks, but there was no improvement in hearing in his right ear., Conclusions: The relatively isolated onset of deafness as well as the severity and persistence of the hearing loss led us to conclude that the hearing loss in this case was likely due to prominent hypoperfusion of the internal auditory artery, with labyrinthine infarction as the earliest event. Vertebrobasilar occlusive disease should be considered in the differential diagnosis of sudden bilateral deafness.

Gastric adenoma is a precancerous lesion of the stomach and its malignant transformation is thought to result from accumulative series of gene alterations. The aim of this study was to determine the pattern of chromosomal changes during gastric carcinogenesis. Pairs of adenoma and carcinoma tissues from 15 gastrectomy cases containing both adenomas and carcinomas in the same (adjacent pairs, 6 cases) and different (non-adjacent pairs, 9 cases) lesions, were analyzed for chromosomal alterations of 39 non-acrocentric chromosomal arms by comparative genomic hybridization (CGH). CGH analysis identified frequent chromosomal alterations in most of the gastric adenomas (14/15, 93%) and all of the carcinomas. The mean number of chromosomal alterations was higher in carcinoma (5.5 for adenoma and 11.7 for carcinoma; P = 0.006, by nonparametric Wilcoxon's test). Losses on the short arm of chromosome 17 were most common in both adenomas (43%) and carcinomas (67%). The pattern of chromosomal alterations in paired gastric adenomas and carcinomas showed greater similarity compared to the non-case pairs and this similarity was increased in the adjacent pairs. Deletion mapping analysis on chromosome 17p also demonstrated that the conserved deletion area was more frequent in the adjacent pairs. Among these 6 adjacent pairs, all had common deletion areas. In contrast, among the 9 non-adjacent pairs, 2 (22%) had common area of deletion, 5 (56%) showed deletion only in the carcinoma, and the remaining 2 (22%) had no deletion on 17p, suggesting diverse genetic changes might be involved in the multiple tumor formation. Our results that common clonal genetic changes between adjacent pairs of gastric adenomas and carcinomas and accumulated genetic changes in the carcinomas provide evidences for the stepwise mode of gastric carcinogenesis through the accumulation of a series of genetic alterations.

We report here three cases of Amanita virosa induced toxic hepatitis. Two of the three cases recovered but the other died 10 days after mushroom ingestion. Since the mortality of Amanita mushroom induced toxic hepatitis is very high, prompt diagnosis and aggressive therapeutic measures should be initiated as soon as possible. Our cases showed that the initial serum aminotransferase levels might not predict the clinical outcome of the patient, but that the prothrombin time (PT) seemed to be a more useful prognostic marker. Close monitoring of aminotransferase levels and PT as well as appropriate therapy are recommended. All three cases showed signs of proteinuria and we were able to characterize mixed tubular and glomerular type proteinuria at 3 or 4 days after ingestion in two cases. Among the previously reported Korean cases of suspected Amanita induced toxic hepatitis, most species could not be identified except for four cases of Amanita virosa. No cases of Amanita phalloides induced toxic hepatitis have been identified in Korea so far.

There is uncertainty and controversy about the relationship between skin type and development of vitiligo. The present study was undertaken to study whether vitiligo patients have a different skin type than the control group. We investigated the skin types of 201 Korean vitiligo patients and 70 healthy Korean volunteers. Skin type was determined by the skin phototyping method proposed by Fitzpatrick. Compared to normal controls, skin type II was significantly less frequent and skin type V was quite common in the vitiligo group. These results suggest that people with dark skin have a higher probability of developing vitiligo than people with light skin.

Klinefelter syndrome (KS) is often associated with various neoplasms, especially germ cell tumors. Mediastinum is the most favored site of extragonadal germ cell tumors with KS, which is somewhat different from those without KS. The retroperitoneal germ cell tumor in KS is very rare. A five-month-old boy with an abdominal mass was found to have a retroperitoneal tumor. After surgical removal, he was diagnosed to have mature cystic teratoma. Cytogenetic study of his peripheral lymphocytes revealed that his karyotype was consistent with KS. This case suggests that patients with KS might be at risk of having germ cell tumors in sites other than mediastinum. It also suggests that all cases with these tumors should be screened for the presence of karyotypic abnormalities, and it might help to assess the exact correlation between germ cell tumors and KS, and to treat them accordingly.

Cell surface adhesion molecules are thought to play an important role in establishing intercellular contacts that are necessary for immunological reactions. Intercellular adhesion molecule-1 (ICAM-1, CD54) is a crucial adhesion molecule in mediating cell to cell adhesion during inflammatory responses, including non-MHC-restricted cytotoxicity. In this study, the sICAM-1 levels of ten healthy control subjects and seven generalized active vitiligo patients were measured by ELISA. The sICAM-1 levels were also correlated with the clinical courses in 33 patients with active vitiligo, who received systemic steroid treatment for 3 months. The average serum level of sICAM-1 was significantly higher in patients with active vitiligo than in the healthy control subjects. The sICAM-1 levels significantly decreased after systemic steroid treatment in the clinically improved group. These results suggest that immune activation is involved in active vitiligo and that changes of sICAM-1 levels can be a marker in the course of vitiliginous lesions.

We determined the prevalence of antibodies to beta(2) glycoprotein-I (beta(2) GPI) in sera of 57 patients with primary or secondary immune thrombocytopenia positive for platelet antibody (PAIgG) and in 16 healthy control subjects. Both isotypes (IgG and IgM) of anti-beta(2) GPI were detected by means of semiquantitative ELISA and platelet antibodies were measured by means of flow cytometry using FITC-labeled anti-human IgG. Six (10.5%) of 57 patients with immune thrombocytopenia had anti-beta(2) GPI, whereas none of the 16 healthy subjects had anti-beta(2) GPI. Four were positive for IgM anti-beta(2) GPI, one for IgG anti-beta(2) GPI, and one was positive both for IgM and IgG anti-beta(2) GPI. There was no significant association between the presence of anti-beta(2) GPI and the severity of thrombocytopenia. Our findings suggest that some patients with immune thrombocytopenia have anti-beta(2) GPI in addition to the increased PAIgG; however, the results do not support a major role for anti-beta(2) GPI in the pathogenesis of immune thrombocytopenia.

We report on a case of clear cell acanthoma that developed above a preexisting melanocytic nevus. Although melanocytic nevi can be complicated by the presence of several different types of epithelial or appendageal tumors, there have been no reported case of clear cell acanthoma combined with a nevus. Interestingly, in this case the clear cell acanthoma had a polypoid configuration, an unusual finding.

The objective of this study was to determine the effects of oviductal fluid and heparin on sperm penetration and the characteristics of spermatozoa. The addition of oviductal fluid and heparin to the fertilisation medium decreased sperm penetration and the mean number of spermatozoa in penetrated eggs. The number of spermatozoa firmly bound to zona pellucida was also decreased in the presence of oviductal fluid and heparin. Chlortetracycline (CTC) fluorescence patterns were used to determine the incidence of capacitation and the acrosome reaction. The proportion of capacitated and acrosome-free spermatozoa increased when spermatozoa were exposed for 1.5 and 3 h to oviductal fluid and heparin. In contrast heparin alone did not increase the number of capacitated spermatozoa at these time points. These results suggest that factor(s) in oviductal secretions reduce polyspermic fertilisation and the number of spermatozoa that will penetrate porcine oocytes. The reduction of polyspermic penetration by oviductal secretions may be due to a reduced number of spermatozoa in the fertilisation medium with an intact acrosome.

The physical activities of daily living are a final outcome of many functions and dependent on many factors. This study was aimed at exploring the relationships of motor function, dementia, education, age, and cognitive function to the physical activities of daily living in 67 elderly people residing in an institution in Taegu, Korea. Their mean ( +/- SD) age was 75.6 +/- 8.1 and 24 (35.8%) were men. Twenty-eight (41.8%) were classified as having definite cognitive impairment, 17 (25.4%) as having questionable impairment, and 22 (32.8%) as having no impairment by the Korean version of the mini-mental state examination. Of the aforementioned 5 variables, the Motoricity Index could account for 42% of the Barthel Activities of Daily Living variance. If the modified Blessed Dementia Rating Scale was included in the multiple regression, the accountable portion of the Activities variance increased by 4% only. Using the 2 variables, regression equation, y = 0.248 x chi 1-0.359 x chi 2-6.250 (y: Barthel Activities of Daily Living score, chi 1: Motoricity Index score, chi 2: modified Blessed Dementia Rating Scale score) could be produced. Conclusively, the physical activities of daily living of elderly people could be related mainly with motor function of the limbs and severity of dementia.